Since 1990, 21 states have seen an increase in the death rate among people aged 20 to 55. In five states—Kentucky, Oklahoma, New Mexico, West Virginia, and Wyoming—the probability of early death among young adults rose by more than 10 percent in that time frame. Meanwhile, in New York and California, young and middle-aged people became much less likely to die in the same time period. The authors note that opioids, alcoholism, suicide, and kidney disease—which can be brought on by diabetes and alcoholism—were the main factors leading to the increases in early deaths.